The only thing I actually read, though, was an item about how Demi Moore and Ashton Kutcher plan to adopt a child. Said an anonymous source: “[A]fter all the disappointments and the IVF treatments, everyone is really excited that they are making their dream come true. It's a win-win situation.”

Perhaps. Perhaps not. Later reports in US magazine and elsewhere noted that on a Twitter page believed to be Moore’s (but how can you be sure?), the 46-year-old movie star married to the 31-year-old movie star had denied the story. “Been asked all day so to clear up rumors,” read the tweet, “we are not adopting a child but what a gift if that at some time was something we wanted to do!”

I suspect the question of more children for Moore, and a first for Kutcher, is far more complicated than a tweet can express. And if it isn’t now, it might well become that way.

We didn’t adopt, either. We talked about adoption. I read about how it works, the tens of thousands of dollars required. I knew a couple who traveled to Brazil, only to have the birth mother change her mind. We had a small window: could we even be approved if Sheri was in her fifties and me in my thirties? Adoption seemed daunting, impossible, fraught with risk; I suppose, in its way, the dull, familiar ache of childlessness was easier.

When I fell in love with Sheri, I understood the likelihood that I’d never father a child. When I was 27, that was an acceptable sacrifice for a life with a woman as remarkable as Sheri.

Nearly twenty years later, I know I’ve missed out on something fundamental to human experience. Sheri has, too. Though I would not change a whit of my past if it meant losing Sheri, I sometimes try to understand who that young man was, and why he made the decisions he did. I question his motives, his wisdom. Was he selfish, not wanting to share his life with a child? Was he afraid of the responsibility? Was he immature?

Was I? Am I?

With age, I’ve found ways to bring children and young people into my life. I teach, of course, and I’ve enjoyed participating in the growth to adulthood of countless young people. I’m blessed to have a marvelous nephew and niece who live too far away and whom I wish could see more often. I volunteered for nearly five years through Big Brothers, which brought into my life a wonderful boy who has grown into a young man I’m proud to call a friend.

All to the good. Though none of it fills a gap I feel only vaguely, that I can’t define. I see parents with children, I try to imagine how it must be. But I can’t. I’ve no frame of reference. What I know is what it means to be childless, and I know this status in a way parents never can.

In a poem called “The Block” from her book Near Changes, the poet Mona Van Duyn opens with the line “Childless, we bought the big brick house on the block, / just in case. We walked the dog.”

Like the speaker in Van Duyn’s poem, we, too, have lived in neighborhoods full of children where instead of driving a van to a soccer game we walked dogs. We have walked three. Tinker is gone, euthanized in 1999. Kaimin is seven. Ozark, crippled and exhausted, will likely be dead this Tuesday. I’ve never treated our dogs as anything but dogs, but they are beloved dogs, and I wonder whether how I love them is something like how parents love children; both kinds of love grow for a creature that has depended on you and, sometimes, wanted to please you.

“The years bloomed by,” Van Duyn writes, “the old dogs were put to sleep. We bought a scoop to walk our new pup on his leash …”

"Then the long, warm, secret descent beganand we slid along with it. ‘We need a last dog,’ I said,‘but I can’t face it.’ "

Thanks so much, Miss Kerry, for your kind words. We're glad to hear them and to have you as a reader. We post at least once a week (though sometimes more often), usually on the weekends. I hope you'll stick with us ...

I'm in a relationship with a man 15 years younger than me, I have two children from my previous marriage who live him dearly but he has recently started to get really down about not having his own child. It is forcing us apart as I can't change my age or the situation. Do you have any advice ??

Hello, Anonymous. First, we apologize for taking so long to respond to your comment. One reason is that you caught us in the midst of a life transition--nothing dramatic, just time consuming. The other reason is that we weren't certain how to respond. We're not advice-givers, generally, in part because we don't feel expert in anyone else's lives (not even, oftentimes, in our own).

What I can tell you is that, yes, like your partner, I've often felt down about not having children. But always in that equation is the preposition "with Sheri." She's my wife, my partner, and I can't imagine having children with anyone but her.

Lots of couples who are childless have included a partner who felt differently than I do. I've known relationships to end over one partner's inability or unwillingness to have children. Maybe other readers of this blog have been in that situation and understand better the impulses that would drive one partner away from another over childlessness. Maybe they could help you understand the pressures your partner feels.

I suppose my only advice would be to keep asking questions and come to understand--and help him to understand--what he needs that a child might answer. Are your kids already older, and he'd like an infant in his life? Adoption might answer that. Are your children both daughters and he'd like a boy to raise? Perhaps Big Brothers would help satisfy that need. Does he feel some strong need to pass on his DNA? Did he always imagine himself as part of the common image of a family, and does he find himself uncomfortable in this other version?